Exp Clin Endocrinol Diabetes 2013; 121 - P31
DOI: 10.1055/s-0033-1336701

The value of endoscopic ultrasound and other imaging techniques compared to adrenal vein sampling regarding therapeutic decisions in patients with primary aldosteronism

VG Fourkiotis 1, A Schumacher 1, SR Galan 1, PH Kann 1
  • 1Division of Endocrinology & Diabetology, Philipp's University Marburg, Faculty of Medicine, University Hospital Marburg UKGM, Marburg, Germany

Context: Primary aldosteronism (PA) is the most common form of secondary hypertension and potentially curable. Differentiation between the two most common subtypes, aldosterone-producing adenoma (APA) and idiopathic adrenal hyperplasia (IHA) can be challenging, but is of great importance since adrenalectomy is only convenient in patients with APA. It is known that MRI and CT are not dependable in imaging the adrenal glands, especially when evaluating small (< 5 mm) lesions. Therefore endoscopic ultrasound (EU) may be a useful complemental examination method in patients with PA.

Design and patients: 76 (39 f/37 m) patients with PA were studied with a mean age of 55.6 ± 12.6 years. Diagnosis of PA was based on a repeatedly elevated aldosterone-renin ratio in the absence of affecting medication and an elevated urinary aldosterone excretion rate. For subtype differentiation orthostasis test was performed in 45 (59%), abdominal ultrasound in 46 (61%), MRI in 32 (42%), CT in 45 (59%), and EU in 75 (99%) of all 76 patients. The final analysis included 22 (29%) patients in whom adrenal vein sampling (AVS) was performed.

Results: 14 patients had undergone both AVS and CT imaging. Congruent diagnostic results were found in nine (64%) individuals. Of 10 patients examined with MRI and AVS, six (60%) had a unilateral disease or idiopathic form of PA, respectively in both examination methods. Abdominal ultrasound showed a concordance rate of 43% (14 vs. 6) compared to AVS in detecting APA. EU revealed congruent results to AVS in 13 APAs and three forms of IHA (22 vs. 16, concordance rate 73%).

Discussion: EU showed the highest concordance rate to AVS of all four analyzed imaging techniques. It is important to know that although AVS is considered the gold standard for subtype differentiation in PA, it is technically demanding and complex to interpret (Schirpenbach 2009). Further analysis is required to interpret the long-term outcome of all 76 patients after treatment.